JPH062992B2 - Discoloration treatment agent for bleaching - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a discoloration treatment agent for bleaching, which is used for the purpose of imparting fashionability to an indigo-dyed article such as blue jeans. The present invention relates to a color changing method using the same.

(Problems to be Solved by Prior Art and Invention) In recent years, in the processing of blue jeans, bleaching has become one of the extremely important processing steps in order to meet various fashionable demands from users. The bleaching process of this blue jeans utilizes the property that the indigo dye used for dyeing turns into isatin by the oxidizing agent and is erased. As the oxidizing agent for such a purpose, a chlorine-based oxidizing agent such as sodium hypochlorite and potassium permanganate have been used conventionally.

However, in the bleaching process of blue jeans, if a treatment with a strong decolorization degree is performed using a chlorine-based oxidizing agent such as sodium hypochlorite, it is necessary to use a large amount of the oxidizing agent or the processing time is delayed, It has been pointed out that problems such as a large amount of reducing agent used in the reduction step after the oxidation treatment, deterioration of the working environment, and deterioration of the tear strength of the product due to deterioration of the blue jeans fibers to be treated are pointed out. .

Moreover, when potassium permanganate is used as an oxidant,
Although it is possible to perform decolorization treatment in a shorter time than chlorine-based oxidizers, the manganese dioxide produced by the decomposition of potassium permanganate remains in the fabric after the treatment, so that the skin of the wearer Etc. there is a problem of toxicity.
Further, with such a conventional oxidizer, although the change in the lightness of the indigo color, that is, the tone from the dark color to the light color can be adjusted, the color change, which is the change in the color tone, is impossible.

[Structure of the Invention] (Means and Actions for Solving the Problems) Therefore, the present inventor has conducted extensive studies as to a bleaching treatment agent that solves the above-mentioned problems, and as a result, in the bleaching treatment of blue jeans or the like, oxidation was performed. When a bromine-based oxidizing agent is used alone or in combination with another oxidizing agent, the above problems relating to the bleaching treatment are solved, and further, a blue jeans product having a color tone that cannot be produced by the conventional bleaching treatment. It has been found that the above-mentioned results are obtained, and the color change treatment agent for bleaching of the present invention has been completed.

That is, when the bromine-based oxidizing agent of the present invention is used in combination with the chlorine-based oxidizing agent in the discoloration treatment, the amount of the oxidizing agent used is reduced as compared with the case where the chlorine-based oxidizing agent is used alone, and the treatment time is shortened, and It has been found that the degree of bleaching is improved and also that it gives good results in the tear strength test of blue jeans products. Even more surprisingly, it has been found that the use of the bromine-based oxidizing agent of the present invention in bleaching makes it possible to impart a new color tone that cannot be produced by conventional oxidizing agents.

The bleaching treatment agent of the present invention is in the form of a solid, a liquid or a slurry in which a solid is present, and contains a brominated oxidant as an essential component.

The bromine-based oxidizing agent in the present invention, when made into an aqueous solution,
It is one or more anions selected from bromic acid, bromic acid, hypobromic acid and bromide, and in that case, sodium, potassium and the like are generally present as cations.
As the bromine-based oxidizing agent having such characteristics, compounds such as sodium bromate, potassium bromate, sodium bromate, potassium bromate, sodium hypobromite, potassium hypobromite, and bromine Ratio with alkali such as sodium hydroxide or potassium hydroxide 0.9: 2
To 1.1: 2, or a mixture of an inorganic bromide such as sodium bromide or potassium bromide and a chlorine-based oxidizer such as sodium hypochlorite.

In the present invention, the dosage form of the bromine-based oxidizing agent can be appropriately selected from solid, liquid, or slurry in which solid is present in the liquid. When the bromine-based oxidizing agent of the present invention is used as a formulation, 1 to
The content is preferably 80% by weight, more preferably 5 to 70% by weight. When the concentration of the bromine-based oxidant in the above-mentioned preparation is low, it is difficult to adjust the concentration of the bromine-based oxidant in the bleaching solution to an appropriately high level, which is not preferable. Here, the concentration of the bromine-based oxidant is the sum of the concentrations of the anions of the bromine-based oxidant measured by the ion chromatography method.

In addition, additives such as chelating agents such as sodium ethylenediaminediacetic acid and sodium ethylenediaminetetraacetic acid, which are commonly used in bleaching agents, can be added to the bromine-based oxidizing agent formulation. The concentration of the additive in the preparation is preferably 1 to 50%,
More preferably, it is 5 to 20%.

The bromine-based oxidizing agent of the present invention can be used alone or in combination with other oxidizing agents in the bleaching treatment, and its embodiment is exemplified by the following method.

A first embodiment is a method of treating an indigo dyeing agent in a bleaching solution in which both the bromine-based oxidizing agent of the present invention and a chlorine-based oxidizing agent such as sodium hypochlorite are present. . In this case, in the bleaching solution, the total amount of the brominated oxidant of the present invention is 0.00
It is preferable to use 5 to 5%, more preferably 0.0
It is used at a concentration within the range of 1 to 1%, and the chlorine-based oxidizing agent is used in an effective chlorine amount of 0.01 to 2%, preferably 0.05 to
It is preferably used at a concentration within the range of 0.5%. If the concentration of the bromine-based oxidant is low, the effect of promoting decolorization is not sufficient, and if the concentration is high, environmental problems such as gas generation occur, which is not preferable. Also,
When the concentration of the chlorine-based oxidant is low, the decolorizing effect is insufficient, and when the concentration is high, problems such as deterioration of working environment due to generation of gas and the like occur, which is not preferable. The treatment conditions in this case are a temperature of 0 to 70 ° C., preferably 40 to 60 ° C., a treatment time of 1 to 60 minutes, preferably 5 to 2
0 minutes can be used.

In a second aspect, the dyed fabric is treated with the first treatment solution in which the bromine-based oxidant of the present invention is present alone, and then the other oxidant such as a chlorine-based oxidant is added in the second treatment solution.
The bleaching method may be performed by using the treatment solution of 1. In this case, the first bleaching solution containing the bromine-based oxidant of the present invention is used to treat only a part of the dyed material, and then another oxidant such as a chlorine-based oxidant is present. By performing the treatment with the second bleaching solution, it is possible to obtain a highly fashionable product in which a part of the article to be dyed is treated with a strong decolorization degree. Such a treatment is difficult by the conventional method of using the oxidizing agent alone, and is possible only when the brominated oxidizing agent of the present invention is used in combination. In this case, the concentration of the brominated oxidant in the first bleaching solution was 0.01 due to the same reason as in the first embodiment.
It is preferable to use at a concentration in the range of ~ 5%, 0.0
The range of 5 to 0.5% is more preferable. Further, the concentration of the oxidizing agent in the second bleaching solution is 0.01 to 2%, more preferably 0.05 to 0.5%, as the effective chlorine amount when the oxidizing agent is a chlorine-based one. A range of concentrations is preferred.
The reason is that the decolorization contrast of the indigo dyeing object after bleaching can be made clear. The treatment conditions in the first treatment and the second treatment used in this case are that the temperatures are 0 to 70 ° C. and 0 to 70, respectively.
C., preferably 20-60.degree. C., 40-60.degree. C., and the treatment time is 1-30 minutes, 1-60 minutes, preferably 1-5 minutes, 5-20 minutes.

Furthermore, as a third aspect, there is a method of performing bleaching using a treatment solution in which the bromine-based oxidizing agent of the present invention is present alone. Regarding the concentration of the bromine-based oxidizing agent in the bleaching solution in this case, it is preferable to use the range of 0.1 to 5%, preferably 0.5 to 3% for the same reason as above, and the treatment conditions are The temperature is 20 to 70 ° C., preferably 40 to 60 ° C., and the treatment time is 10 to 60.
Minutes, preferably 15 to 30 minutes.

The pH of the bleaching solution of the present invention is generally adjusted to pH 3 to 12, but preferably adjusted to pH 3.5 to 10. This pH adjustment can be performed using an acid such as mineral acid or acetic acid, or an alkali such as sodium hydroxide.

When preparing the bleaching solution of the present invention, various additives used in ordinary bleaching solutions can be added. For example, a chelating agent such as sodium ethylenediamine diacetate or sodium ethylenediamine tetraacetate is added in an amount of 0.01 to 0.5%, preferably 0.05 to 0.5%.
It can be added to the bleaching solution at a concentration of 0.1%.

The treatment method of bleaching the indigo dyeing product using the treatment agent of the present invention is not limited at all, a method using a conventional washer, pumice stone impregnated with various oxidizing agents in the washer, etc. Methods such as the "stone washing method (Chemical Stone method)" in which a porous solid substance is present, the dipping method in which the material is immersed in a treatment solution, or the like, or A method of applying the bleaching solution to the indigo material to be dyed with a brush or the like, a method of processing by spraying, and the like can be adopted.

Further, when the bleaching process is carried out by the treating agent of the present invention, pretreatment such as water washing, stone washing, etc., which is usually carried out in the bleaching process, gives good results as the object of the present invention.

After performing bleaching of the indigo dyeing product using the treatment agent of the present invention, under the same conditions as in normal bleaching,
Treat with reducing agent, rinse, wash with detergent,
Appropriate post-treatment combined with softening treatment and the like can be performed, and then a drying step can be further performed.

By using the bleaching treatment agent of the present invention in combination with a chlorine-based oxidizing agent such as sodium hypochlorite, it becomes possible to shorten the processing time in bleaching and enable processing with high bleaching degree. At the same time, the specific tear strength of the indigo-dyed product after bleaching is also improved. Furthermore, when a bromine-based oxidizer is used alone or in combination with other oxidizers, conventional chlorine-based oxidizers such as green-based or golden-based oxidants can be obtained by changing processing conditions such as concentration. It is possible to obtain a product with a color tone that could not be obtained depending on the product. For example, in a bleaching solution containing 5 to 10% of the bromine-based oxidizing agent of the present invention alone, a liquid temperature of 40 to
A product having a golden color tone is obtained by performing the treatment at 60 ° C. for 60 to 80 minutes, and in a bleaching solution containing 3 to 5% of the bromine-based oxidizing agent of the present invention alone, a liquid temperature of 40 to 60.
When the treatment is carried out at 60 ° C. for 60 to 80 minutes, a product having a deep golden color tone is obtained. Further, for example, using the first bleaching solution containing the bromine-based oxidizing agent of the present invention alone in an amount of 2 to 5%, only a part of the dough is treated at a liquid temperature of 20 to 30 ° C. for 5 to 10 minutes, and then, Sodium hypochlorite 0.1-0.2
% In a second bleaching solution containing 40% of liquid temperature 40-60 ° C.
When the treatment is carried out for 10 to 15 minutes, a product having a part of yellow-green color in the navy blue fabric is obtained.

Although details of the mechanism of the effect of such a brominated oxidizer are unknown, the present invention is to find a treatment agent that can perform a useful function in bleaching of indigo dyeing products, and its industrial use. The above utility is great.

Further, when the bromine-based oxidizing agent of the present invention is used, no harmful residual substance remains in the product after bleaching, so there is no problem in terms of safety.

(Examples) Next, the present invention will be described with reference to specific examples, but the present invention is not limited to these examples. In the following, "%" means "% by weight".

The method for measuring the concentration of the bromine-based oxidant and the method for testing the specific crack strength of the product in the present invention are as follows.

Method for measuring the concentration of bromine-based oxidant 0.1 g of a sample was accurately weighed, 40 ml of water and 0.1 N-KOH were added thereto to adjust the pH to 8-9, and then the volume was adjusted to 100 ml, and 5 ml thereof was added. Was accurately weighed and 100 ml was used as the sample solution.
100 μl of this solution was injected into a column of ion chromatography (manufactured by Toso Corporation, CCPD column), and from the peak area and the calibration curve prepared in advance, the ion of each bromine-based oxidant in the sample solution was determined. The concentration was quantified. The sum of the concentrations (by weight) of the respective ions of bromic acid, bromic acid, hypobromous acid, bromide, etc., determined by this method was taken as the concentration of the brominated oxidant in the present invention.

Tear strength test of products Test pieces of indigo dyeing products that have been bleached are subjected to post-treatments such as treatment with a reducing agent and washing with water.
After further drying, the tear strength was measured by the method of JIS L 1096 B (Bendurum method).

Examples 1 to 3 and Comparative Examples 1 to 3 The following treatment was carried out using a test piece of indigo dyed blue jeans (tear strength: about 5 kg) cut into a size of 10 cm × 10 cm.

The bleaching solution is 30ml, 20ml, 10ml of sodium hypochlorite aqueous solution (effective chlorine amount 12%), respectively.
A solution was prepared by adding water to this and making the total amount to 1 to obtain treatment solutions of Comparative Examples 1 to 3. Further, to these sodium hypochlorite solutions, as the bromine-based oxidizing agent of the present invention, sodium bromate was added in an amount so as to have various concentrations in the bleaching solution, and the results were obtained in Examples 1-1 to 1-1.
It was a treatment solution of 3-4.

The bleaching solution having various compositions described above was placed in a glass beaker, the liquid temperature was adjusted to 50 ° C., and then a bleaching treatment was performed by immersing a test piece of blue jeans. The time required for decolorizing the light blue color obtained by ordinary bleaching was measured and used as the processing time.

The results of the above Examples and Comparative Examples are shown in Tables 1 to 3 below. In the table below, the amount of NaClO solution represents the amount (ml /) of the sodium hypochlorite aqueous solution (effective chlorine amount 12%) to the bleaching solution 1, and the bromine-based oxidant concentration is the bleaching solution. The concentration (% by weight) of the brominated oxidant concentration of the present invention in 1 is measured by the above-mentioned measuring method.

Example 4 and Comparative Example 4 Using the bleaching solution under the same conditions as in Example 1 and the same method, the treatment time required for decolorizing a test piece of blue jeans to a pale blue color and the tear strength of the obtained product. Was measured. The results are shown in Table 4 below.

Example 5 Indigo-dyed blue jeans test pieces were bleached for 30 minutes in the same manner as in Examples 1 to 3 while changing the composition and concentration of the oxidizing agent in the bleaching solution.

The composition of the bleaching solution, and the color and tear strength of the product bleached using it are shown in Table 5 below.
Shown in.

Example 6 A test piece of indigo-dyed blue jeans similar to that of Example 1 was previously patterned with a brush using the bromine-based oxidizing agent of the present invention at a concentration of 0.01%, and then the test piece was used as a comparative example. The sample was treated by immersing it in a bleaching solution similar to that of No. 1 for 30 ml / ml of NaClO solution for 10 minutes.

As a result, a bleaching process was performed in which the portion treated with the brominated oxidant was subjected to a treatment with high bleaching degree.

[Effects of the Invention] As described in detail above, by using the treatment agent containing the brominated oxidant of the present invention, it is possible to improve the bleaching of indigo-dyed articles such as blue jeans, and to obtain the conventional method. It is possible to obtain a product having a color tone that was not obtained.

Claims (2)

[Claims] 1. A discoloration treatment agent for bleaching an indigo dyeing object, which comprises a bromine-based oxidizing agent. 2. The discoloration treating agent according to claim 1, which is 0.005 to 5.
A method for discoloring an indigo dyeing object, which comprises immersing the indigo dyeing object in a treatment liquid containing 1% by weight.